Mortal Kombat: Deception is a fighting game developed and published by Midway as the sixth installment for the Mortal Kombat (MK) series. Deception was developed for the PlayStation 2 and Xbox in October 2004, while a Nintendo GameCube version waspublished in March 2005. Mortal Kombat: Deception follows the storyline from the fifth installment, Deadly Alliance; It features the revival of the Dragon King Onaga, who starts conquering the realms featured in the series after defeating the Deadly Alliance, the sorcerers Quan Chi and Shang Tsung who were the main antagonists in the previous game, and the Thunder God Raiden, defender from realm. As such, the surviving warriors from the previous titles join forces to confront Onaga.

26 characters are playable in the game with 9 making their first appearance in the series. Deception contains several new features in the series such as chess and puzzle games with the MK characters and an online mode. The Konquest Mode role-playing game (RPG) already shown in Deadly Alliance now follows the life of Shujinko, a warrior who is deceived by the Onaga to make a search of forty years to give him more powers while he trains with several characters from the series. During November 2006, Midway released Mortal Kombat: Unchained, a port for the PlayStation Portable, which added new characters to the game.

Co-creator from the series Ed Boon mentioned that Deception was made to be an unpredictable fighting game as it gives new features such the mini-games and the Konquest Mode which has now more interaction with the plot from the series. Several parts from Deadly Alliance such as combos, or arenas were redesigned to be more realistic as well as more interactive. Deception has been well received by video game reviewers, who praised the fights and the new features. However, the Konquest Mode also received criticism for poor voice acting. Several publications have also awarded the game as the best fighting game from 2004.